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1.
J Phycol ; 58(3): 449-464, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35247270

RESUMO

Fallacia is distinguished morpho-anatomically from Navicula sensu lato based on the possession of an H-shaped chloroplast, lateral sterna and a finely porous conopeum, but whether this genus is monophyletic is still in question. Three new Fallacia species are described based on morphology and SSU rRNA and rbcL gene sequences: Fallacia tateyamensis sp. nov., Fallacia bosoensis sp. nov. and Fallacia laevis sp. nov. We performed the first comprehensive molecular and morphological phylogenetic analyses of 31 Fallacia species based on 11 new sequences from six species and 23 morphological characters. We also documented the detailed morphogenesis of Fallacia for the first time. Fallacia is not monophyletic. Both morphological and DNA sequence data supported the separation of Rossia from Fallacia, while the phylogenetic position of Pseudofallacia is uncertain. We recognized four morphogroups in Fallacia by morphological and molecular phylogenetic analyses. Ancestral character reconstruction indicated that diatoms in Sellaphoraceae evolved from the possession of two lateral narrow parallel depressions covered by narrow nonporous conopea, to lyre-shaped canals covered by wide porous conopea. Lanceolate canals and the presence of areolae in canals evolved multiple times independently.


Assuntos
Diatomáceas , Diatomáceas/genética , Filogenia , Análise de Sequência de DNA
2.
Sensors (Basel) ; 18(10)2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30274187

RESUMO

Biometric authentication is popular in authentication systems, and gesture as a carrier of behavior characteristics has the advantages of being difficult to imitate and containing abundant information. This research aims to use three-dimensional (3D) depth information of gesture movement to perform authentication with less user effort. We propose an approach based on depth cameras, which satisfies three requirements: Can authenticate from a single, customized gesture; achieves high accuracy without an excessive number of gestures for training; and continues learning the gesture during use of the system. To satisfy these requirements respectively: We use a sparse autoencoder to memorize the single gesture; we employ data augmentation technology to solve the problem of insufficient data; and we use incremental learning technology for allowing the system to memorize the gesture incrementally over time. An experiment has been performed on different gestures in different user situations that demonstrates the accuracy of one-class classification (OCC), and proves the effectiveness and reliability of the approach. Gesture authentication based on 3D depth cameras could be achieved with reduced user effort.

3.
Ann Vasc Dis ; 10(2): 152-154, 2017 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29034044

RESUMO

A 72-year-old woman with a history of malignant lymphoma was referred to our hospital for the treatment of a bronchial artery aneurysm. Computed tomography (CT) scan showed a round, 30 mm-diameter fusiform aneurysm with two tortuous inflow arteries. We deployed thoracic stent grafting to cover the orifice of the two inflow arteries without transcatheter bronchial arterial embolization. Postoperative CT scan revealed complete thrombosis of the aneurysm. Although further follow-up is mandatory, this may be considered a viable treatment option in cases wherein the bronchial artery aneurysm is anatomically difficult to treat.

4.
Soc Neurosci ; 12(2): 102-112, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26899265

RESUMO

Social cognitive skills are indispensable for successful communication with others. Substantial research has determined deficits in these abilities in patients with mental disorders. In neurobiological development and continuing into adulthood, cross-cultural differences in social cognition have been demonstrated. Moreover, symptomatic patterns in mental disorders may vary according to the cultural background of an individual. Cross-cultural studies can thus help in understanding underlying (biological) mechanisms and factors that influence behavior in health and disease. In addition, studies that apply novel paradigms assessing the impact of culture on cognition may benefit and advance neuroscience research. In this review, the authors give an overview of cross-cultural research in the field of social cognition in health and in mental disorders and provide an outlook on future research directions, taking a neuroscience perspective.


Assuntos
Cognição , Comparação Transcultural , Transtornos Mentais/psicologia , Percepção Social , Humanos , Habilidades Sociais , Teoria da Mente
5.
Ann Vasc Dis ; 7(3): 300-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25298833

RESUMO

OBJECTIVES: We present our experience of endovascular surgery for traumatic aortic injury and the results of our procedures. MATERIALS AND METHODS: From January 2009 to December 2013, we performed endovascular repairs of traumatic thoracic aortic injury on 5 male patients 16-75 years old (mean, 50.8), two of whom were young. Three of the patients had multiple organ injuries. The mean interval time to the operation is 22.0 hours (range, 10-36). All patients underwent endovascular repair with heparinization. The isthmus regions were seen in three cases and all of them were needed left subclavian artery (LSA) coverage. In the two young patients, the deployed stent graft was 22 mm (22.2% oversizing for diameter of aorta) and 26 mm (36.8% oversizing), respectively. RESULTS: The procedures were successful in all patients, with no early mortality, paraplegia or stroke. During 3-63 months (mean, 30.8) follow-up period, no one experienced stent graft-related complications. One patient with LSA coverage experienced arm ischemia but the symptom improved with time. CONCLUSION: Endovascular surgery for traumatic thoracic aortic injury can be performed safely with low mortality or morbidity even in young small aorta. Accumulation of clinical experience and evaluation of long-term outcomes are necessary.

6.
Dent Mater ; 30(7): e189-98, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24679985

RESUMO

OBJECTIVE: Polymerization shrinkage developed in vertical and horizontal directions after light activation of light-curing composite restorative materials. The purpose of this study was to examine the effects of vertical and horizontal polymerization shrinkage on: (a) dimensional changes of resin composites in tooth cavities; (b) shear bond strengths to enamel and dentin; and (c) marginal gap width in a non-reacting Teflon mold. METHODS: Vertical and horizontal polymerization shrinkage in tooth cavities were measured immediately (3 min) after light activation. With the same time lapse, shear bond strengths to enamel and dentin and marginal gap widths in Teflon mold were also measured. RESULTS: There was a significant correlation between vertical and horizontal polymerization shrinkage (r=0.647, p=0.043) in the tooth cavity. Composite materials which produced small vertical shrinkage also produced smaller horizontal shrinkage. Composite materials which produced small vertical shrinkage in the tooth cavity exhibited greater shear bond strengths to both enamel (r=-0.697, p=0.025) and dentin (r=-0.752, p=0.012). Composite materials which produced smaller horizontal shrinkage produced smaller marginal gap widths in the Teflon mold (r=0.829, p=0.003). No relationships were observed between horizontal shrinkage in the tooth cavity and shear bond strengths to both enamel and dentin (p>0.05). SIGNIFICANCE: During the early stage of setting (<3 min) in tooth cavities, the vertical shrinkage of light-activated composite restorative materials was correlated with horizontal shrinkage.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Polimerização , Humanos , Técnicas In Vitro , Teste de Materiais
7.
PLoS One ; 7(7): e42024, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848693

RESUMO

The sea slug Plakobranchus ocellatus (Sacoglossa, Gastropoda) retains photosynthetically active chloroplasts from ingested algae (functional kleptoplasts) in the epithelial cells of its digestive gland for up to 10 months. While its feeding behavior has not been observed in natural habitats, two hypotheses have been proposed: 1) adult P. ocellatus uses kleptoplasts to obtain photosynthates and nutritionally behaves as a photoautotroph without replenishing the kleptoplasts; or 2) it behaves as a mixotroph (photoautotroph and herbivorous consumer) and replenishes kleptoplasts continually or periodically. To address the question of which hypothesis is more likely, we examined the source algae for kleptoplasts and temporal changes in kleptoplast composition and nutritional contribution. By characterizing the temporal diversity of P. ocellatus kleptoplasts using rbcL sequences, we found that P. ocellatus harvests kleptoplasts from at least 8 different siphonous green algal species, that kleptoplasts from more than one species are present in each individual sea slug, and that the kleptoplast composition differs temporally. These results suggest that wild P. ocellatus often feed on multiple species of siphonous algae from which they continually obtain fresh chloroplasts. By estimating the trophic position of wild and starved P. ocellatus using the stable nitrogen isotopic composition of amino acids, we showed that despite the abundance of kleptoplasts, their photosynthates do not contribute greatly to the nutrition of wild P. ocellatus, but that kleptoplast photosynthates form a significant source of nutrition for starved sea slugs. The herbivorous nature of wild P. ocellatus is consistent with insights from molecular analyses indicating that kleptoplasts are frequently replenished from ingested algae, leading to the conclusion that natural populations of P. ocellatus do not rely on photosynthesis but mainly on the digestion of ingested algae.


Assuntos
Clorófitas/citologia , Clorófitas/metabolismo , Gastrópodes/metabolismo , Processos Fototróficos , Plastídeos/metabolismo , Simbiose , Animais , Gastrópodes/classificação , Filogenia , Estações do Ano
8.
Phys Chem Chem Phys ; 13(35): 16005-14, 2011 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-21829826

RESUMO

The chemiluminescence (CL) mechanism of oxidophenyl-substituted 1,2-dioxetane was investigated by performing TD-DFT calculations on biradicals of three model compounds. We propose a novel mechanism of CL in which excitation of a dissociative intermediate by infrared radiation (IRE) of the surrounding solvent is considered. The excitation energies and oscillator strengths (f-values) were estimated for intermediates along the reaction coordinate (Rx). The difference in efficiencies of CL between syn- and anti-isomers of m-oxidophenyl-dioxetane is explained using the difference in potential curves of the singlet excited states (S) and the IRE mechanism. At the point where the biradical of the anti-isomer decomposes into two fragments, the interaction between the S and triplet (T) states is induced by a significant back electron transfer (BET) from the dioxetane group to the oxido-phenyl group and the S(1) excited state is stabilized and CL efficiency is enhanced. In the syn-isomer, the barrier in the S(1) potential curve to reach the final CL state is higher than for the anti-isomer, which reduces the efficiency. The poor CL yield for the p-isomer is ascribed to a much higher barrier in the potential curve of the S(1) state.

9.
J Org Chem ; 76(12): 5006-17, 2011 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21574649

RESUMO

Thermally stable rotamers of bicyclic dioxetanes bearing 6-hydroxynaphthalen-1-yl (anti-5a and syn-5a), 3-hydroxynaphthalen-1-yl (anti-5b and syn-5b), and 5-hydroxy-2-methylphenyl groups (anti-5c and syn-5c) were synthesized. These dioxetanes underwent TBAF (tetrabutylammonium fluoride)-induced decomposition accompanied by the emission of light in DMSO and in acetonitrile at 25 °C. For all three pairs of rotamers, the chemiluminescence efficiency Φ(CL) for anti-5 was 8-19 times higher than that for syn-5, and the rate of CTID (charge-transfer-induced decomposition) for anti-5 was faster than that for syn-5. The chemiluminescence spectra of the rotamers for 5a and 5c, respectively, were different. This discrepancy in the chemiluminescence spectra between rotamers can presumably be attributed to the difference in the structures of de novo keto imide anti-14 and syn-14 in an excited state, which inherit the structures of the corresponding intermediary anionic dioxetanes anti-13 and syn-13. The important difference in chemiluminescence efficiency between anti-5 and syn-5 is discussed from the viewpoint of a chemiexcitation mechanism for CTID of oxidophenyl-substituted dioxetane.


Assuntos
Éteres Cíclicos/química , Compostos Heterocíclicos com 2 Anéis/química , Luminescência , Modelos Moleculares , Conformação Molecular
10.
Kyobu Geka ; 64(2): 130-3, 2011 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-21387618

RESUMO

We reported on a case of 80-year-old woman who suffered from severe acute respiratory failure. A chest computed tomography (CT) revealed arch aneurysm and innominate artery pseudoaneurysm, which severely compressed main bronchus and trachea. After tracheal intubation in the emergency room, respiratory status improved rapidly. We immediately performed total arch replacement using deep hypothermia, circulatory arrest and the arch first technique. The postoperative course was uneventful, and stenosis of trachea resolved. Arch aneurysm associated with acute trachea occlusion is very rare and employing deep hypothermia, circulatory arrest and the arch first technique is useful for such atypical arch aneurysms.


Assuntos
Falso Aneurisma/complicações , Aneurisma Roto/complicações , Aneurisma da Aorta Torácica/complicações , Tronco Braquiocefálico , Estenose Traqueal/etiologia , Doença Aguda , Idoso de 80 Anos ou mais , Feminino , Humanos
11.
J Phycol ; 47(5): 999-1008, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27020181

RESUMO

Many of the genes that control photosynthesis are carried in the chloroplast. These genes differ among species. However, evidence has yet to be reported revealing the involvement of organelle genes in the initial stages of plant speciation. To elucidate the molecular basis of aquatic plant speciation, we focused on the unique plant species Chara braunii C. C. Gmel. that inhabits both shallow and deep freshwater habitats and exhibits habitat-based dimorphism of chloroplast DNA (cpDNA). Here, we examined the "shallow" and "deep" subpopulations of C. braunii using two nuclear DNA (nDNA) markers and cpDNA. Genetic differentiation between the two subpopulations was measured in both nDNA and cpDNA regions, although phylogenetic analyses suggested nuclear gene flow between subpopulations. Neutrality tests based on Tajima's D demonstrated diversifying selection acting on organelle DNA regions. Furthermore, both "shallow" and "deep" haplotypes of cpDNA detected in cultures originating from bottom soils of three deep environments suggested that migration of oospores (dormant zygotes) between the two habitats occurs irrespective of the complete habitat-based dimorphism of cpDNA from field-collected vegetative thalli. Therefore, the two subpopulations are highly selected by their different aquatic habitats and show prezygotic isolation, which represents an initial process of speciation affected by ecologically based divergent selection of organelle genes.

12.
Gen Thorac Cardiovasc Surg ; 55(8): 325-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17867278

RESUMO

We report the first successful outcome of a patient undergoing concomitant surgery for a left atrial myxoma and a squamous cell carcinoma of the lung. Preoperative evaluations revealed lung cancer and a left atrial tumor of undetermined origin. An operation to excise both cardiac and pulmonary tumors was performed. The cardiac tumor was first resected with the aid of cardiopulmonary bypass. The histopathological diagnosis was myxoma. Resection of the left upper pulmonary lobe and mediastinal lymph nodes followed. The postoperative course was uneventful, and the patient is well without evidence of recurrence 7 years after the operation.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Cardíacas/cirurgia , Neoplasias Pulmonares/cirurgia , Mixoma/cirurgia , Idoso , Carcinoma de Células Escamosas/complicações , Ponte Cardiopulmonar , Átrios do Coração , Neoplasias Cardíacas/complicações , Humanos , Neoplasias Pulmonares/complicações , Masculino , Mixoma/complicações , Resultado do Tratamento
13.
Dent Mater J ; 26(4): 514-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17886455

RESUMO

The aim of this study was to develop an effective primer to improve the adhesive property between all kinds of dental metal alloy and resin cement. To this end, we synthesized N,N'-dimethacryloylcystine (NDMCC) which had both disulfide functional group (to improve adhesion between precious metal alloy and resin) and carboxyl group (to improve adhesion between non-precious metal alloy and resin). With the presence of SuperBond C&B, the adhesion between precious, semi-precious, and non-precious dental metal alloys and resin cement was improved when compared to the untreated controls. However, the adhesive property between all types of dental metal alloy and resin cement was not improved with Panavia 21EX. In particular, reduced bond strength in the case of non-precious metal alloy was speculated to arise from the acid-base neutralization reaction between the carboxyl group of NDMCC and the amine present in the polymerization initiator system of Panavia 21EX.


Assuntos
Ligas Dentárias/química , Colagem Dentária/métodos , Cimentos de Resina/química , Teste de Materiais/métodos , Propriedades de Superfície
14.
Dent Mater J ; 26(6): 785-91, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18203482

RESUMO

In the current study, we examined the cytocompatibility of eight vinyl esters as candidate plasticizers for producing phthalate- and ethanol-free tissue conditioners. We measured the estrogenic activity and cytotoxicity of vinyl esters in human fibroblasts and keratinocytes using an E-screen assay and a mitochondrial dye conversion assay, respectively. We also assessed the cytotoxicity of three prototype materials and commercially available tissue conditioners on human fibroblasts grown in collagen gels. Finally, we measured the effects of these materials on the expression of cytokines in three-dimensional cultures by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assays. None of the tested vinyl esters had estrogenic activity. Vinyl octanoate and vinyl pivalate were the least cytotoxic of the eight tested vinyl esters. In the same vein, a prototype tissue conditioner containing vinyl octanoate had equivalent or weaker cytotoxicity and induction of cytokine expression than conventional materials.


Assuntos
Ésteres/toxicidade , Fibroblastos/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Plastificantes/toxicidade , Condicionamento de Tecido Mole Oral/efeitos adversos , Compostos de Vinila/toxicidade , Células Cultivadas , Ésteres/química , Estrogênios não Esteroides/análise , Humanos , Interleucina-1beta/análise , Interleucina-6/análise , Plastificantes/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Compostos de Vinila/química
15.
J Pharmacol Exp Ther ; 317(2): 562-70, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16436501

RESUMO

We evaluated the pharmacological profiles of FMS586 [3-(5,6,7,8-tetrahydro-9-isopropyl-carbazol-3-yl)-1-methyl-1-(2-pyridin-4-yl-ethyl)-urea hydrochloride], a novel tetrahydrocarbazole derivative as a neuropeptide Y (NPY) Y5 receptor antagonist. This compound showed a highly selective in vitro affinity for Y5 (IC(50) = 4.3 +/- 0.4 nM) relative to other NPY receptor subtypes like Y1 or Y2. Its binding to Y5 was found to be fully antagonistic from cyclic AMP accumulation assays in human embryonic kidney 293 cells. Pharmacokinetic analysis revealed sufficient oral availability and brain permeability of this compound accompanied with clear dose relation. We attempted to assess the selectivity of FMS586 and, thereby, to infer the physiological role of Y5 in the following feeding experiments in normal rats. An intracerebroventricular injection of NPY and Y5-selective agonist peptide induced acute and robust feeding responses in satiated rats, and prior administration of FMS586 at the doses from 25 to 100 mg/kg clearly inhibited these responses by approximately 55 and 90%, respectively. This compound also showed dose-dependent but transient suppression in natural feeding models of both overnight fasting-induced hyperphagia and spontaneous daily intake. FMS586 did not modulate food intake induced by the topical injection of norepinephrine, galanin, or gamma-aminobutyric acid receptor agonist muscimol to the paraventricular nucleus. In addition, we confirmed the Y5-specific activity profile of FMS586 by immunohistochemical analysis. Taken together, we propose not only that our compound potentially expresses specific blockade of central Y5 signals but also that Y5 receptor would certainly contribute to physiological regulation of food intake in normal rats, as suggested from its origin.


Assuntos
Depressores do Apetite/farmacologia , Carbazóis/farmacologia , Hiperfagia/tratamento farmacológico , Compostos de Metilureia/farmacologia , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Administração Oral , Animais , Depressores do Apetite/farmacocinética , Ligação Competitiva , Carbazóis/farmacocinética , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Humanos , Hiperfagia/metabolismo , Imuno-Histoquímica , Masculino , Compostos de Metilureia/farmacocinética , Estrutura Molecular , Ensaio Radioligante , Ratos , Ratos Wistar
17.
Cell Microbiol ; 5(6): 395-404, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12780777

RESUMO

Genetic and functional studies have indicated that the type IV secretion system (TFSS) of Helicobacter pylori forms a secretion complex in the cell envelope that protrudes towards the outside in order to inject CagA protein into gastric epithelial cells. However, the proposed structural model is based on partial amino acid homology with the components of the Agrobacterium tumefaciens TFSS. Therefore, we undertook the identification of the structural features of the TFSS exposed on the surface of H. pylori and found that filamentous structures present on the bacterial surface are related to the secretion apparatus. Using immunofluorescence microscopy with antibodies directed to tyrosine-phosphorylated CagA (pY-CagA) and Hp0532 (VirB7) in the infection assay, pY-CagA signals were detected just below the host cell-attached bacteria, where Hp0532 (VirB7) signals were detected as co-localized, suggesting that the CagA injected into the host cell through the TFSS apparatus is still mostly confined to the areas just below the attached bacteria after being phosphorylated. Furthermore, the filamentous structures on bacterium were found to be associated with Hp0532 (VirB7) or Hp0528 (VirB9), the major components of TFSS, by immunogold electron microscopy. These results strongly suggest that the H. pylori TFSS apparatus is a filamentous macromolecular structure protruding from the bacterial envelope.


Assuntos
Proteínas da Membrana Bacteriana Externa/análise , Helicobacter pylori/química , Antígenos de Bactérias/análise , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/análise , Células Cultivadas , Infecções por Helicobacter/microbiologia , Helicobacter pylori/citologia , Helicobacter pylori/ultraestrutura , Humanos , Microscopia Imunoeletrônica/métodos , Modelos Genéticos , Mutação , Fosforilação , Transporte Proteico , Tirosina/metabolismo
18.
Ann Thorac Surg ; 75(4): 1205-8; discussion 1208-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12683564

RESUMO

BACKGROUND: The endoventricular circular patch plasty (Dor procedure) applies to patients with a left ventricular dysfunction due to an ischemic dilated ventricle. In the present study, we analyzed left ventricular energetics in patients who underwent the Dor procedure. METHODS: We measured left ventricular contractility (end-systolic elastance; Ees), afterload (effective arterial elastance; Ea), and efficiency (ventriculoarterial coupling; Ea/Ees, and the ratio of stroke work and pressure-volume area; SW/PVA) based on the cardiac catheterization data before and after the Dor procedure in 8 patients with a postinfarction dyskinetic anterior left ventricular aneurysm. Concomitant procedures included coronary artery bypass grafting in all patients, mitral valve repair in one patient, and cryoablation in one patient. End-systolic elastance (Ees) and Ea were approximated as follows: Ees = mean arterial pressure/minimal left ventricular volume, and Ea = maximal left ventricular pressure/(maximal left ventricular volume-minimal left ventricular volume), and thereafter Ea/Ees and SW/PVA were calculated. The left ventricular volume was normalized with the body surface area. RESULTS: End-systolic elastance (Ees) increased after the Dor procedure (from 1.15 +/- 0.60 to 1.86 +/- 0.84 mm Hg x m2 x mL(-1), p < 0.01), thus resulting in an improvement in Ea/Ees and SW/PVA (from 2.94 +/- 1.11 to 1.64 +/- 0.49, p < 0.01, and from 0.426 +/- 0.110 to 0.559 +/- 0.082, p < 0.01, respectively), even though Ea did not substantially change (from 2.96 +/- 0.78 to 2.74 +/- 0.55 mm Hg x m2 x mL(-1), p = 0.4). CONCLUSIONS: Left ventricular contractility and efficiency improves after the Dor procedure in patients with a dyskinetic anterior left ventricular aneurysm. However, afterload does not change. The use of appropriate afterload-reducing therapy thus plays an especially important role in the management of patients who undergo the Dor procedure.


Assuntos
Aneurisma Cardíaco/cirurgia , Ventrículos do Coração/cirurgia , Disfunção Ventricular Esquerda/cirurgia , Função Ventricular Esquerda/fisiologia , Função Ventricular , Adulto , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Estudos Retrospectivos
19.
Mol Cell ; 10(4): 745-55, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12419219

RESUMO

CagA delivered from Helicobacter pylori into gastric epithelial cells undergoes tyrosine phosphorylation and induces host cell morphological changes. Here we show that CagA can interact with Grb2 both in vitro and in vivo, which results in the activation of the Ras/MEK/ERK pathway and leads to cell scattering as well as proliferation. Importantly, this ability of CagA is independent from the tyrosine phosphorylation, which occurs within the five repeated EPIYA sequences (PY region) of CagA. However, the PY region appears to be indispensable for the Grb2 binding and induction of the cellular responses. Thus, intracellular CagA via its binding to Grb2 may act as a transducer for stimulating growth factor-like downstream signals which lead to cell morphological changes and proliferation, the causes of H. pylori-induced gastric hyperplasia.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Antígenos de Bactérias , Proteínas de Bactérias/metabolismo , Helicobacter pylori/metabolismo , Proteínas/metabolismo , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células COS , Divisão Celular , Linhagem Celular , Movimento Celular , Tamanho Celular , Proteína Adaptadora GRB2 , Helicobacter pylori/genética , Humanos , Mutação , Fosforilação , Fosfotirosina/metabolismo , Ligação Proteica , Proteínas/genética , Transdução de Sinais
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